I think TIFU is one of those communities that can only exist when you have a larger userbase. There's only so many times one individual can post a good fuck up .
!source_ports@lemmy.sdf.org - Source ports for retro PC games, that allow them to run on different OSs, and/or with updated "modern" features and quality of life additions
!laserdisc@lemmy.sdf.org - Anything LaserDisc related. I have a huge collection, and love preservation efforts.
I'm always open to right-hand info link exchanges with other similar communities, as well.
Also an underrated community that I like to use occasionally:
!lemmy411@lemmy.ca to ask about whether specific communities exist/are around that you may not be having much luck finding (say, due to unique naming or nobody on your instance has joined it so it doesn't appear in search).
Lastly there's my own little community I threw together awhile ago that I'm not sure how to grow where you can ask around for stuff similar to other stuff you're into:
Hi there! Looks like you linked to a Lemmy community using a URL instead of its name, which doesn't work well for people on different instances. Try fixing it like this: !rarepepes@lemmy.world